Gauge for checking external dimensions of circular work



March 21, 1950 w. KUPPERSMITH 2,501,130

G E F CHECK EXTERNAL DIMENSI OF C ULAR WORK Filed March 31, 1945 4 Sheets-Sheet 1 F. w. KUPPER$METH 25L113 GAUGE FOR CHECKING EXTERNAL DIMENSIONS OF CIRCULAR WORK 4 Sheets-Sheet 2 I "led. March 51,

F. W. KUPPERSMITH GAUGE FOR CHECKING ER DIMENSIONS OF CIRCU W March 21,, 1950 4 Sheets-Sheet 5 Filed March 31, 1945 INVEN TOR. J w

BY jag W4 MZ- March 2%,1950 F. w. KUPPERSMITH 2,501,130

GAUGE FOR CHECKING EXTERNAL DIMENSIONS OF CIRCULAR WORK Filed March 31, 1945 4 Sheets-Sheet 4 INVENTOR.

Patented Mar. 21, 1950 UNITED STATES PATENT QFFICE GAUGE FOR CHECKING EXTERNAL DIMEN- SIONS OF CIRCULAR WORK 2 Claims.

This invention relates to check gauges, more particularly to pneumatically-operated check gauges or comparators for readily and accurately comparing with a standard, or measuring, threaded parts or substantially cylindrical unthreaded parts, and the invention has for an object the provision of improved gauges of this character.

In a prior application, Serial No. 467,438, filed November 30, 1942, and issued as Patent Number 2,397,494, in the name of the present applicant and entitled Measuring device, various types of pneumatically-operated measuring devices and gauges, together with an improved pressure regulator and indicator, are shown and described. Although certain of the basic principles disclosed in this prior application are employed in gauges embodying the present invention, the improved gauges herein disclosed are particularly adapted for the accurate measuring or comparing of cylindrical and threaded workpieces, and are of such simple and sturdy construction as to render them useful under various conditions and by relatively unskilled operators.

In carrying out the invention in one form, a gauge is provided comprising a pair of spaced apart oppositely disposed work-engagin elements, together with means for adjusting the spacing of the elements in order that workpieces of difierent diameters may be inserted therebetween, one of th elements being resiliently mounted for limited movement by a workpiece upon insertion of the workpiece between the elements. The gauge is provided with a fluid passageway having an outlet opening, and fluid under pressure is supplied to the assageway at a point remote from the outlet opening. Associated with the movable work-engaging element are means for variably restricting the outlet opening to vary the back pressure in the passageway, and indicatin means responsive to the back pressure in the passageway are utilized to indicate the size of the workpiece being checked. Preferably the outlet from the passageway is in the form of an outwardly diverging substantially conical seat, and a ball is disposed in the s at for movement with respect thereto so as variably to restrict the outlet and thereby vary the back pressure in the passageway, th position of the ball being controlled by the movable workengaging element.

In order properly to position workpieces within the gauge for checking, a backing member is provided for limitin the extent of insertion of the workpiece between the Work-engaging elements, the backing member being mounted rearwardly of the work-engaging element so as to position the workpiece with the elements engaging it in diametric relation, and means are provided for adjusting the position of the backing member in conformance with adjusted spacings of the work-engaging elements so that workpieces of different diameter, when inserted between the work-engaging element, will be engaged by the backing member on a radius substantially at right angles to the diameter engaged by the checking elements.

For a more complete understandin of the invention, reference should now be had to the drawings in which:

Fig. 1 is a side elevational view partly in section of a thread gauge embodying the present invention;

Fig. 2 is a detail view of one of the workengaging elements employed in the gauge of Fig. 1;

Fig. 3 is a side elevational view similar to Fig. 1 of another form of thread gauge embodying the invention;

Fig. 4 is a front elevational view of the gauge shown in Fig. 3;

Fig. 5 is a side elevational view partly in section of another gauge embodying the invention and adapted for the checking of unthreaded cylindrical parts;

Fig. 6 is a front elevational view of the gauge shown in Fig. 5;

Fig. '7 is an elevational view partly in section of still another form of thread gauge embodying the invention;

Fig. 8 is a fragmentary front elevational view of the gauge shown in Fig. '7;

Fig. 9 is a side elevational view partly in section of still another form of thread gauge embodying the invention;

Fig. 10 is a back elevational view of the gauge shown in Fig. 9;

Fig. 11 is a front elevational view of the gauge shown in Fig. 9;

Fig. 12 is a fragmentary elevational view taken substantially along the line |2--|2 of Fig. 9;

Fig. 13 is an elevational view similar to Fig. 9 but showing the gau e adjusted for the checking of workpieces of larger diameter;

Fig. 14 is a side elevational view of still another gauge embodying the invention; and

Fig, 15 is a sectional view taken substantially along the line l5l5 of Fig. 14.

Referring now to Fig. l of he drawings, the

invention is shown as embodied in a thread gauge for checking or comparin threaded parts, which gauge comprises a generally C-shaped frame having upper and lower legs 2| and 22, respectively. Carried by the lower leg 22 is a workengaging roller or element 23 which is constructed as shown more in detail in Fig. 2. The thread engaging element 23 is of a type well known in the art consisting of a roller or cylinder 24 having a plurality of substantially V-shaped annular ridges 25 extending from the surface of the roller, the size and spacing of the ridges being such that when brought into contact with a threaded part of the correct pitch these ridges will engage the thread substantially at the pitch line. The roller 24 is mounted on a shaft 25 which shaft is carried by a substantially U- shaped frame 26, the mounting of the roller on the shaft and the mounting of the shaft in the frame being somewhat loose to permit the roller 24 to adjust itself to th angularity of the threads on the part being checked.

As shown in Fig. 1, the frame 26 of the threadengaging element 23 is mounted on a pin 21 which is slidably adjustable in a drilled hole in the end of the leg 22 of the frame 20. Suitable locking means are provided for securing the pin 21 in various adjusted positions relative to the leg 22, and although various types of locking means may be provided, the means 28 shown in Fig. 1 are preferably of the general type illustrated in Fig. 15 which will be more fully described hereinafter.

Mounted in the upper leg 2| of the frame 20 for limited movement with respect thereto, is a thread-engaging element 29 which is identical with the thread-engaging element 23 except that the roller supporting frame is provided with a rearwardly-extending lug or tail 30. The pin 3| on which the thread-engaging element 29 is mounted extends entirely through a suitable aperture in the leg 2| and at its upper end is provided with a notch 32 for receiving the end of a leaf spring 33 which is suitably secured to the upper surface of the leg 2| as by a screw 34, the spring 33 being arranged to urge the pin 3| downwardly to a position in which the free end of the spring engages the upper surface of the arm 2|. In the drawings the pin 3| and the thread-engaging element 29 are shown in their uppermost position to which they have been moved by insertion of a threaded workpiece be tween the opposed work-engaging elements 23 and 29, the workpiece being diagrammatically indicated in the drawing by the concentric circles Also carried by the frame 20 is a third workengaging element which constitutes a backing member 36 and which may be identical with the work-engaging element 23. The backing member 36 is carried by a pin 31 arranged for axial adjustment in an angularly extending bore 38 in the frame 20. Adjacent its outer end the bore 38 is enlarged, as shown, and threaded to receive an adjusting screw 39, having a predetermined number of threads per inch for moving the backing member 36 to various adjusted positions, the inner face of the screw 39 being adapted to abut the end of the pin 31. Suitable locking means 28 are also associated with the pin 37 to secure the backing member 36 in any desired position after adjustment thereto by the adjusting screw 39.

The backing member 36 is employed, as shown in Fig. 1, to limit the extent to which the workpiece may be inserted between the elements 23 and 29. The bore 38 and the supporting pin 37 for the backing member extend at an angle of 45 degrees with respect to a line drawn through the centers of the work-engaging elements 23 and 29, and consequently adjustment of the pin 31 in the bore 38 will cause the backing member 36 to move equal distances in horizontal and vertical directions. By reason of this 45 degree angularity the backing member 36 may readily be adjusted to a position in which it will engage the workpiece 'on a radius substantially at right angles to the diameter of the workpiece engaged by the elements 23 and 29. while insuring that the extent of insertion of the workpiece is such .iat the elements 23 and 29 engage the workpiece in diametric relation. Thus, if it is desired to adjust the spacing of the elements and 29 so as to check a threaded workpiece having a pitch diameter A; inch smaller than the workpiece 35, it is necessary only to adjust the workengaging element 23 upwardly 1 inch and to adjust the backing member 36 upwardly and inwardly a distance such that it will have moved inwardly inch and upwardly inch, whereupon it will be positioned to engage the smaller workpiece on a radius at right angles to the diameter engaged by the elements 23 and 29.

Extending through a portion of the upper leg 2| of the frame 2! is a passageway 43 that terminates in an outlet which, as shown, comprises a conical seat 4| in a lower surface of the leg 2|. Disposed in the conical seat for engagement by the arm or tail 30 on the element 29 is a valve or ball 42 which is normally biased downwardly by a spring 43, and it will be observed that upward and downward movement of the element 29 when engaged by a work piece will cause movement of the ball 42 toward and away from the conical seat 4| so as to vary the degree of restriction of the outlet by the ball. The other end of the passageway is connected in any suitable manner to a source of fluid under substantially constant pressure, and a suitable pressure gauge is connected to the passageway to indicate variations in the back pressure produced by the movement of the ball .2.

Although any suitable pressure source and pressure indicator may be employed, Fig. 1 diagrammatically shows a combined pressure regulator and indicating instrument 44 of the type described and claimed in the above referred to prior application Serial No. 467,438. This pressure regulator and indicating instrument is connected, as diagrammatically indicated by the line 45 in Fig. l, to a suitable source of air pressure and is likewise connected, as indicated by the line 46 in Fig. 1, to the passageway 40. The regulator supplies to the passageway 40 a substantially constant volume of fluid under substantially constant pressure, and consequently movement of the ball 42 to vary the degree of restriction of the outlet to the passageway 40 causes a variation in the back pressure which is indicated on the dial of the measuring instrument.

In Fig. 1 the taper of the conical seat 4| is shown as approximately 30 degrees with respect to the axis of the passageway, but other angles may be employed depending upon the sensitivity of response desired in the instrument 44. It will be apparent that as the angle of taper increases, i. e., the conical seat 4| approaches a flat seat, the change in the degree of closure or opening provided by a predetermined movement of the ball 42 will increase, and therefore the change in the back pressure provided by a predetermined movement of the ball will likewise increase. Accordingly, it is necessar to correlate the calibrations of the pressure-responsive instrument M with the taper of the conical seat 4| to obtain the desired response.

The embodiment of the invention illustrated in Figs. 3 and 4 is in general similar to the gauge of Fig. 1, and the same reference numerals are employed to indicated the same or corresponding parts. The gauge of Figs. 3 and 4 is adapted for use in checking threaded parts having either square or V-shaped threads, and in place of the work-engaging elements 23 and 29 of Fig. 1, the supporting pins ill and 2? carry anvil type workengaging elements All and as. As shown, the work-engaging element fill consists of a support ing block 43 carried on the pin 2'! and having a dovetail groove in the upper Surfaces thereof in which groove there is disposed the thread-engaging anvil 5B, the upper surface of which is provided with a plurality of properly shaped parallel ridges 5|. In order that the anvil 58 may be removed and replaced by a similar anvil having different shaped or different size thread-engaging ridges thereon, a pair of locking screws 52 is provided which threadedly engage the block ll with a portion of the head of each screw extending over the end of the dovetail portion of the anvil 58 to retain the anvil in the dovetail groove while permitting a slight longitudinal movement thereof in order that the anvil 58 may properly engage the threads of the part being tested.

The work-engaging element 58 consists of a supporting block 53 which is in general. similar to the block 49 but which is provided with a lug or tailpiece 54 for engaging the spring pressed ball 42. Likewise the work-engaging element 4b includes a thread-engaging anvil 50 and suitable locking screws 52 which are identical with the corresponding parts of the work-engaging element 4?. The backing member in this embodiment of the invention includes a U-shaped frame 55 which is mounted on the adjustable pin 3'! and supports a smooth surfaced cylindrical roller 56.

In Fig. 3 a workpiece is diagrammatically shown by the concentric circles 57, and it will be observed that the work-engaging element 53 has been moved by the workpiece 5'! to its uppermost position so that the ball 42 substantially closes the passageway it, the cylinder 56 of the backing member engaging the surface of the workpiece 5! so as to position it with the work-engaging elements 41 and 48 in diametric relation to the workpiece. Upon removal of the workpiece, the work-engaging element ts will be forced downwardly by the spring 33 and the spring 43 will cause the ball to move downwardly so as to open the outlet from the passageway lil. It will of course be understood that in this embodiment of the invention, as well as in all of the succeeding embodiments to be described hereinafter, the passageway 45 is connected to a suitable source of pressure and a suitable pressure-responsive instrument, as described in connection with the embodiment shown in Fig. l.

The check gauge shown in Figs. 5 and 5 is adapted for use in checking unthreaded cyl indrical parts or similar parts having a circular contour, and comprises a c-shaped frame 58 which is in general similar to the frame it of the previous embodiments and includes opposed legs BI and 62 having aligned drilled holes 83 and 64 therein for slidably receiving suitable pins 65 and 66, respectively. The pin 66 carries on its upper end a work-engaging anvil 61, and suitable locking means 23 are employed for looking the pin 65 in predetermined adjusted positions. The pin 65 in the upper leg ii! carries at its lower end a work-engaging anvil 68 having a slot 69 therein for receiving the free end of a leaf spring is, the opposite end of which is connected to frame M by screws ii, the spring 10 normally biasing the pin 65 and the anvil 68 to the lowermost position shown in Fig. 5.

At its extending upper end the pin E55 carries an arm 12 which, upon movement of the pin 65 relative to the arm 6i, moves toward and away from the outlet of a fluid passageway '83 formed in the frame til. Preferably the outlet of the passageway 13 is formed by an insert or seat 14 having an opening 15 therethrough of restricted diameter. When the pin 65 and the anvil B8 are in the lowermost positions shown in Fig. 5, it will be observed that the arm 12 substantially closes the outlet l5 from the passageway l3 and it will be apparent that if a workpiece such as indicated diagrammaticall by the circle it is forced between the spaced apart work engaging elements 67 and 68, the element fit will be moved upwardly so as to open the outlet l5 and cause a drop in the back pressure in the chamber 13 which, as previously indicated, is connected by a pipe or tube ll to a suitable pressure-responsive instrument and a suitable source of pressure.

In this embodiment of the invention the backing member comprises an adjustable pin 73 having a beveled end is for engaging the workpiece E6, the pin it being mounted in a drilled hole in the frame Ell, which hole extends at an angle of 45 degrees to the center lines of the workengaging elements 57 and (it. The backing member 78 is adjustable along the hole 80 and is provided with suitable locking means 28 as in the previously described embodiments, and in order to insure that the beveled face l9 will always occupy a vertical position, the hole in the frame 39 is provided with a keyway or slot 8! for receiving a key as carried by the backing member 78.

The embodiment of the invention shown in Figs. 7 and 8 is in some respects similar to the embodiment of Fig. l and employs a number of identical parts which are indicated by the same reference numerals as were employed in Fig. 1. In place of the upper work engaging element 29 of Fig. 1, however, the gauge shown in Figs. '7 and 8 includes a work-engaging element 83 having a frame 84 provided. with a slot 35 for receiving the free end of a leaf spring ill; which is substantially identical with the spring it of Figs. 5 and 6. This workengaging element is mounted on a pin 3'! carried by the upper arm 88 of a generally G-shaped frame 89, and the upper end of the pin 81' carries an arm which is identical with the arm 12 of the embodiment shown in Fig. 5. The upper leg 83 of the frame 89 includes a fluid passageway 3b which terminates in a conical seat or outlet Si in which is disposed a ball or valve 93 biased in an upward direction by a coil spring 96.

In Fig. 7 the worlnengaging element iii is shown in its lowermost position to which it is urged by the spring at, and the ball 93 substantially closes the outlet of the fluid passageway 96. If the workpiece to be checked is inserted between the work-engaging elements 23 and 8;; to a position in which it engages the backing member 36, it

will be observed that as the workpiece is moved from the position indicated by the broken line circle 95 to the position indicated by the similar circle 96, the work-engaging element 83 will be forced upwardly and the spring 94 will move the ball 93 outwardly in the conical seat so as to effect a drop in the back pressure in the passageway 96. In Figs. 9 to 13, inclusive, a thread gauge is shown which is adapted for a somewhat greater range of adjustment than the previously de-- scribed gauges. In this embodiment of the invention, the generally C-shaped frame comprises a pair of frame members 9? and 88 which are pivotally connected together, as shown best in Fig. 10, so that the opposite ends of the members 91 and as, which form the upper and lower ends of the C-shaped frame, may be adjusted toward and away from each other. In order to provide the pivotal connection and likewise provide means for locking the frame members various adjusted positions, the frame members 9'! and 98 are provided with aligned apertui' a hollow spinning or tube 99, the are flanged outwardly to retain icing drilled :e'ive screw IE2, "aded so as to be Each of and the block I86 'c" threadedly engaged by the blocks I01] and MI is shown, and it screw It?! is ti i6 1 iii to". will be obtained v I member or spinnin with the frame in against pivotal mo. ement. -i lar me: .ber 23 may be provid tapered surface and the lock ES! may at s wedging action expand the tubular ht engagement o lock them d, the tubut an inner s and tapered or subsimilar wedging 'ghtening of the stantlally I action will be 0 screw Hi2.

n employs the and 29 as the embodiment sho n in similar parts have been iden reference numerals. In this embodiment of the invention, nt arrangement of the backing 1r frame member 3 ear 28.? adapted to be straddled by the bifurcated end of a link Iil i (Fig. 12), one side of the bifurcation being threaded to receive a suitable screw which extends through the other side of the bifurcation and through a suitable aperture in the ear 1&3 to provide a pivotal mounting for the link I6 3. Similarly, the frame member 98 is provided with an ear I86 adapted to be straddled by the corresponding ends of a pair of links I07, one of the links IU'I, as shown best in Fig. 12, being threaded to receive another screw I65 which passes through the other link IE1 and a suitable aperture in the ear I 56 to provide a pivotal mounting for the links I07.

The free ends of the links I64 and II are apertured to receive a shaft or pin I98 which serves pivotally to connect the links together, and which likewise forms a support for a pair of threadengaging rollers I09 which form the backing member for the gauge. The rollers I09 are preferably provided with V-shaped ridges similar to the ridges 25 on the roller 24 of Fig. 2. It will be apparent that when the frame members 91 and 98 are adjusted to vary the spacing between the work-engaging elements 23 and 29, the links H24 and I0! will pivot about the screws I05 so as to move the backing rolls I08 toward or away from the work-engaging elements 23 and 29. In Fig. 9 a threaded workpiece of predetermined diameter is indicated by the concentric circles I I0 and in Fig. 13 the gauge is shown after adjustment so as to receive a threaded workpiece of larger diameter indicated diagrammatically by the concentric circles I I I.

Due to the fact that the pivot pins or screws I115 for the links It! and II]? move on a different radius than the work-engaging elements 23 and 29, when the frame members 97 and 98 are pivotally adjusted with respect to each other, the inward and outward movement of the backing rolls I99 will, within a limited range of adjustment, automatically correspond to the spacing of the work-engagingelements 23 and 29 so as properly to position the workpieces of different diameters between these elements. Outside of this limited range of adjustment, however, proper positioning of the backing rolls I09 would not be obtained, and accordingly the ears I03 and I06 are provided with elongate slots H2 and II3, respectively through which the pivot pins or screws I95 extend. Thus, after the spacing of the workengaging elements 23 and 29 has been adjusted, the screws I05 may be loosened and the angular position of the links may be adjusted by moving the screws I along the slots II2 and H3 until the backing rolls we are properly positioned. Tightening of the screws I05 draws the bifurcated portions of the link I04 and the ends of the two links It"! together so as to clamp the links I04 and It? in the desired position. This clamping action. may in some cases be sufficient to retain the frame members 9'! and 9B in their respective adjusted positions, in which case the locking means formed by the blocks I and Hit and the locking screw I02 may be omitted at the pivotal connection of the frame members 9? and 8. It will be observed that the work-engaging element 23 is adjustable with respect to the frame member 98, and minor adjustments of the spacing between the work-engaging elements may be accomplished without varying the relative positions of the frame members merely by adjusting the position of the work-engaging element 23.

In the embodiment of the invention shown in Figs. 14 and 15, the generally C-shaped frame is formed by a pair of frame members II5 and H6 which, instead of being pivotally connected as in the embodiment of Fig. 9, are mounted for relative sliding movement along a pair of supporting pins IIT. In order to lock the frame member H6 in adjusted positions on the supporting pins Hi, the frame member is provided with a transverse aperture II8 (Fig. 15) which extends through the frame member between and in intersecting relation to the apertures H9 through which the supporting pins iI'! extend. Disposed in the transverse aperture I I8 is a pair of locking blocks I 28 and IZI, the inner ends of which are provided with curved surfaces adapted to engage the supporting pins II I. A locking screw I22 is provided. which extends through a suitable hole in the block I2I and threadedly engages a correspondingly tapped hole in the block When the locking screw I22 is tightened, the blocks I20 and IZI are drawn toward each other so as to clamp the supporting pins I I7 against movement relative to the frame member IIB. As indicated in Fig. 14, the frame member I I is provided with similar locking means for engaging the supporting pins i ii. The various locking means 28 shown in each of the other embodiments of the invention are of the same genera1 type as illustrated in Fig. 15, except that they are arranged to engage only one pin instead of a pair of parallel pins as in Fig. 15. -t is thought that the construction and operation of the remaining elements in the gauge shown in Figs. 14 and 15 will be clear from the previous description of other embodiments, similar elements being identified by previously used reference numerals.

In using any of the gauges embodying the invention as a comparator, the gauge is first adjusted by inserting a standard workpiece between the work-engaging elements and adjusting the spacing of the elements so as to give a predeter mined or normal reading on the pressure-respon sive instrument i l. When a workpiece to be checked is thereafter inserted between the workengaging elements, any variations in diameter from the standard workpiece will cause a corresponding variation in the restriction of the outlet of the fluid passageway, and consequently the gauge Mi will indicate the degree of variation. If desired, the various gauges may be used to measure directly the size of workpieces, in which case the indicator instrument :34 may be calibrated to give a direct reading of the size.

It will be observed that each of the gauges herein described and embodied in the present invention is of sturdy construction and embodies only easily adjustable and readily assembled parts. Consequently a compact and sturdy gauge is provided which accurately responds to small variations in the size of the workpieces being checked, and which is not likely to be damaged or rendered inaccurate through improper usage.

While I have shown particular embodiments of my invention, it will be understood, of course, that I do not wish to be limited thereto since many modifications may be made, and I, therefore, contemplate by the appended claims to cover any such modifications as fall within the true spirit and scope of my invention.

Having thus described my invention, what I claim and desire to secure by Letters Patent is:

1. A gauge for checking workpieces of substantially circular contour comprising a pair of frame members connected together for relative movement and shaped to form a substantially C shaped frame, a first work-engaging element mounted on and extending inwardly from one of said frame members, an oppositely disposed work-engaging element mounted on the other of said frame members in spaced relation to said first element, whereby relative movement of said frame members varies the spacing of said workengaging elements to receive workpieces of different diameters, a pair of links pivotally connected together, a backing member supported on the pivotal connection between said links, and means pivotally connecting the respective opposite ends of said links to said frame members with said stantially circular contour comprising a pair of frame members connected together for relative movement and shaped to form a substantially C- shaped frame, a first work-engaging element mounted on and extending inwardly from one of said frame members, an oppositely disposed workengaging element mounted on the other of said frame members in spaced relation to said first element, whereby relative movement of said frame members varies the spacing of said work-engaging elements to receive workpieces of different diameters, means resiliently mounting one of said elements for limited movement by'a workpiece upon insertion between said elments, means responsive to said limited movement of said one element for indicating the size of the workpiece being checked, a pair of links pivotally connected together, a backing member supported on the pivotal connection between said links, and means pivotally connecting the respective opposite ends of said links to said frame members with said links in angular relation to position said backing member rearwardly of said spaced elements for limiting the extent of insertionbetween said elements of a workpiece being checked, whereby relative movement of said frame members causes relative angular movement of said links to adjust said backing member toward and away from said spaced elements, and means for locking said frame members and links against relative movement to position said backing member in accordance with the spacing of said elements.

FRED W. KUPPERSMITI-I.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Great Britain Sept. 10, 1943 

